Many of you need advice on whether to itemize or to take the standard deduction. Itemizers use Schedule A of Form 1040 to write off outlays like real estate taxes and mortgage interest. The standard deduction on Form 1040's line 37 is the amount automatically available without having to itemize.

Just how much is your standard deduction for tax year 2003? It all depends. The allowable amount is based mostly on your filing status (the category you fall into as a filer, such as married filing jointly, married filing separately, single or head of household) and age.

The normal standard deduction amounts are $4,750 for an individual with the filing status of single and $7,000 for a head of household. They are $9,500 for married couples filing jointly or $4,750 if they file separately. The law requires couples filing separately to handle their deductions the same way; if one spouse itemizes, so must the other.

An often-missed break: The $9,500 deduction is also available to someone qualifying as a "surviving spouse" – IRS lingo for a widow or widower who has a dependent child and is entitled to use joint-return rates for two years after the death of a spouse in 2001 or 2002.

Deductions are higher for individuals who have attained age 65 by 2003's close. They increase by $950 for a married person (whether filing jointly, separately or as a surviv­ing spouse) and $1,150 for an unmarried person. Individuals considered blind also are entitled to the additional $950 or $1,150 and more if they are both 65 and blind.

Some examples: The deduction rises from $4,750 to $5,900 for a single person who is age 65 or older, and from $4,750 to $7,050 for a single person who is at least 65 and blind. On a joint return, depending on whether one or both spouses are at least 65, it rises from $9,500 to either $10,450 or $11,400.

Special rules decrease the deduction amounts to as little as $750 for individuals (children and elderly parents, mostly) who can be claimed as dependents on the returns of other persons.

Whether to take the standard deduction or itemize might be a close call for many of you. Complications abound because of nondeductible floors for several categories of itemized deductibles. The floors are all pegged to AGI, short for adjusted gross income.

Itemizers get full deductions for real estate taxes, interest on most home mortgages, charitable contributions and state and local income taxes. But they get only partial write-offs for three categories of expenses: (1) Casualty and theft losses not covered by insurance or otherwise reimbursed are allowable only to the extent such losses exceed $100 (for each casualty or theft), plus 10 percent of AGI; (2) Medical expenses not covered by insurance, reimbursed by an employer or otherwise reimbursed are deductible just for the amount above 7.5 percent of AGI; and (3) Most miscellaneous expenses (a grouping that includes write-offs like return-preparation charges) are allowable only for the portion in excess of 2 percent of AGI.

So an AGI of $100,000 means no deduction for the first: $10,000 of casualty losses; $7,500 of medical expenses; and $2,000 of miscellaneous expenses. But there is a reprieve for gambling losses, a miscellaneous expense allowable just to the extent of gambling winnings. Those losses are not subject to the 2 percent floor.

Forget about deductions for most payments of interest on consumer loans – for example, car payments and credit-card charges. There is a limited exception for interest on student loans. Moreover, there are restrictions on deductions for interest on money borrowed to finance investments – say, margin accounts used to buy stocks.